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Getting started Overview Technical requirements Standards Navigation Classroom tools Lesson plans Handouts Assessment materials Other resources Related activities Content background Trouble-shooting

Assessment materials The following assessment materials are available as printable PDF files (requires Adobe Reader). Pre-Test Post-Test Pre- and Post-Test Answer Key Special Assignment - Exploring Success Optional Assessment Questions A hypothetical scenario: Over the course of many generations, the legs of a particular millipede species evolved to be smaller and smaller, until, finally the species was legless. The species now lacks jointed legs and makes its living burrowing in loose soil and leaf litter. Is the millipede species still an arthropod even though it has lost its jointed legs? Explain your answer in a few sentences. Answer: Yes, the millipede is still an arthropod. Organisms are classified according to their evolutionary history. Since the millipede is descended from the arthropod ancestor, it is still an arthropod, even though it no longer has jointed legs. Do some research on sea urchins (Echinoidea) on the Internet. Are sea urchins arthropods? Back up your answer by listing at least three characteristics that support your conclusion. Cite your sources. Answer: Sea urchins are not arthropods. They have radial symmetry (not bilateral symmetry), tube feet (not jointed legs), an endoskeleton (not an exoskeleton), an unsegmented body, and no head. However, like arthropods, they do have a complete gut. Describe two ways that arthropods might be more successful than humans. Give an example or piece of evidence supporting the idea that arthropods are more successful for each of the two measures of success. Answer: Student answers should focus on longevity, number of species, and variety. Use the Internet to research one non-crustacean arthropod with a specialized appendage. Describe the animal and its body layout. How is the limb specialized and what does it allow the arthropod to do? Cite your sources. Hint:Don’t forget that insects, spiders, scorpions, ticks, centipedes, and trilobites are arthropods. Briefly explain what molting is. Describe one way in which molting is dangerous for arthropods. Answer: Molting is a process in which an animal sheds all or part of its outer covering, which is then regenerated in some way. Molting is dangerous to arthropods because: Molting itself is difficult and the animal might get stuck in its old exoskeleton. During molting, the exoskeleton is soft and the animal can’t defend itself and often can’t get food.